不同耐湿基因型甘蓝型油菜苗期对缺氧胁迫的生理差异响应

【目的】试图阐明不同耐湿基因型甘蓝型油菜苗期对缺氧胁迫的生理差异响应。【方法】试验采用不同耐湿基因型的甘蓝型油菜材料，对发芽种子和幼苗（3叶期）缺氧处理，测定种子发芽性状和幼苗可溶性糖、脯氨酸、相对电导率、丙二醛（MDA）、过氧化物酶（POD）活性、过氧化氢酶（CAT）活性、超氧化物歧化酶（SOD）活性等生理指标。【结果】表明耐湿与不耐湿基因型相比具有显著的差异。缺氧处理后耐湿材料发芽种子具有较高的相对发芽率、相对苗长、根长、苗重和活力指数，而相对电导率较低。3叶期幼苗缺氧处理后，耐湿材料可溶性糖和脯氨酸含量提高幅度显著高于不耐湿材料，MDA和相对电导率则显著较低；耐湿基因型POD活性显著提高，CAT活性显著降低，SOD酶活性有较大幅度提高并显著高于不耐湿材料；不耐湿基因型则相反，POD活性显著降低，CAT活性显著提高，SOD酶活性幅度提高较小。【结论】缺氧胁迫下，甘蓝型油菜耐湿基因型能显著增加渗透调节有机物含量，同时启动活性氧清除系统，减少膜脂化程度，提高抵御缺氧胁迫。

Physiological Reaction Differences of Different Waterlogging- Tolerant Genotype Rapeseed (Brassica napus L.) to Anoxia

The seedlings and germinating seeds of rapeseed (B. napus L.) with different waterlogging tolerance (WT) were used to analysis the physiological reaction in anoxic stress. After 12h anoxic stress to germinated seeds, the waterlogging tolerant genotype was different significantly than susceptive genotype with higher relative root and shoot length, fresh weight, survivor rate and relative vigor index, but lower electrical conductance. Without anoxic stress, the three seedling leaves of WT genotype had lower soluble sugar and similar lever in soluble, proline and malnodialdehyde (MDA) content than susceptive genotype. After 48h anoxic stress to three leaves seedling, the WT genotype showed significant different physiological reactions compared to the susceptive genotype with the rapid increase of soluble sugar and proline contents, lower relative electrical conductivity and MDA content. The different physiological reaction also occured in activities changes of activated oxygen scavenger enzyme, activities of the peroxidase (POD) and superoxide dismutase (SOD) of WT genotype increased rapidly but catalase (CAT) decreased after anoxic stress, where susceptive genotype with similar SOD, increase in CAT but decrease in POD.